1. Field
Embodiments relate to a secondary battery.
2. Discussion of Related Art
Recently, as portable electronic devices have been significantly reduced in size and weight, many studies for secondary batteries used as a power supply of the devices have been conducted. Examples of secondary batteries include nickel-cadmium battery, a nickel-hydrogen batteries, a nickel-zinc batteries, and a lithium secondary batteries. Of those batteries, the lithium secondary battery can be made rechargeable, decreased in size and increase in capacity, and has high operation voltage and energy density per unit weight, such that it has been widely used for high-technology electronic devices.
A rectangular secondary battery of the lithium secondary battery is formed by locating an electrode assembly including an anode plate, a cathode plate, and a separator therebetween in a can together with an electrolyte, and then sealing the upper end of the can with a cap assembly. Further, an insulating case is inserted in the upper end of the can.
The insulating case has a hole for an anode tap and a hole for a cathode tap and is inserted to prevent a short circuit between the top of the electrode assembly received in the can and the bottom of the cap assembly. Further, the insulating case can prevent a short circuit that may be generated by contact between the cathode and anode taps and the inner wall of the can. Further, the insulating case can prevent the electrode assembly from moving within the can.
However, the insulating case can become dislodged and separated from the can when the elasticity of the electrode assembly in the can is excessive. Further, when the thickness of the electrode assembly is large, the top of the can may open causing the insulating case to loosen and separate from the can during transportation. Further, the inner side of the can may be scratched by the outer side of the insulating case and burrs are generated, such that welding between the can and the can assembly is deficient resulting in leakage of the electrolyte.